Breast-drill



P. J. 'u: SUEUB. BREAST DRILL. APPLICATION FILED DEC-7.1917.

, Patented June 15 1920.

PHILIP JOSHUA LE SUEUR, or BRIGHTON, ENGLAND.

BREAST-DRILL.

sex, England, have invented a new and use ful' Improvement in Breast-Drills, of. which the following is a specification.

The principal object of this invention is to provide a 11 htly built and cheap form of breast drill with an efficient form of feed for automatically forcing the drill into. the metal or object to be drilled. a l

A special feature of the invention is the arrangement of parts whereby the depth of the cut of the drill can be quickly adjusted rendering this device specially'useful where small and large drills have'to be used by the operator. 7

Another feature of the invention is the lightness and simplicity of the automatic feed device and the facility with whichthe parts can be removed, or thrown out of gear.

Another important feature of the invention is the smoothness and evenness of the automatic feed, which enables the operator to avoid the breakage of drills and leaving both his hands free to operate and steady the breastidrill.

Referring to the drawings Figure 1 is a front elevation showing all the main features.

Fig. 2 is a perspective view of the bearing. riveted to the lever'in which works the ratchet, showing the action of the ratchet .on the ratchet wheel.

Fig. 3 is also a perspective view of the .ratchet pivotally connected with the bear-' ing showing the action of the ratchet on the ratchet'wheel. I

Fig. 4 is, a sectional elevation of bearing, lever, and frame and end elevation of ratchet and ratchetwheeli- Fig. 5 isa frontelevation of lever showing the adjustable in the lever.

Fig. 6is half sectional, half end elevation of bearing, frame, and gear wheel;

Referring to the drawings: 1 designates the iron frame of the breast drill provided with the usual body rest 2.

The drill 3 is held in position by dinary chuck 4.

The feed rod 5 is movably secured to the brace frame by the bearings A. At the the orouter end of the feed rod is the drilling ta Application filed December 7, 1917.

slide piece for lengthen- Serial No. 205,994.

ble 6, which is designed to slide longitudi- "Specifieati on of Letters Patent. Patented J 16 15 19241 nally on the feed rod and is rendered nonturnable relative to= the feed rodby the thumb screw 7', the end of which engages with the groove 1) in the feed rod. The nut 8 retains the drilling table in position.

The feed screw 16 which is provided with w a ratchet wheel 18 and the thumb screw 19 lntegral therewith, is pivotally attached to the frame, the shank 21 engaging the bear,-

ing 22. The threaded portion 16 engages a threaded hole Fin the feed rod.

V The lever :25 (which may also be described as a lifting plate) is pivotally secured to the frame by the screw 26. The lever ex tends along the frame of the breast. drill and is operated by the lifting or bearing which project from thevdrive wheel 28. The bearing 30 (detail-Fig. 2) preferably riveted to the lever by the rivets 'H in which works the ratchet 32, pivotally mounted on 'the rivet 33 and is kept in resilient contact pins 27 with the ratchet wheel 18 by the spring34- which is secured in position by the rivets 85. They spring 36 retains the lever in position. The plate 38 riveted to frame keeps the lever close to the frame.

In using the breast turns the drive wheelin the usual manner. The lifting pins 27 on the drive'wheel lift the end of the lever 25 and with it the drill the operator l ratchet 82 which engages the ratchet. wheel and turns the feed screw, which acts on the feed rod 5 and forces the drilling table and with it the object to be drilled against the point of the drill. The lifting pins 27 are screwed into the drive wheel .and are detachable. 1

In order to regulate the depth of the feed I have provided the snail eccentric 40 which is pivotally secured to the brace frame by the screw 42. screw 46 to hold it in position. It is obvious that by turnin'gthe snail eccentric 40 and shorteningthe contact of the lever 25 with the pins 27, ratchet on the forcing screw 16 will givethe drill a shallow feed. The snail eccentric is also capable of throwing the'lever out; of gear with the pins 27. acts also as a stop piece for the lever, the spring 36 keeping the lever in contact with the snail eccentric 40.

Referring to Fig. 5 it will be seen that the lever 25 1s provided with a slide piece The snail eccentric The slot 44 allows the the action of the lever and '48. This slide piece is adjustable and is k i designed to engage the snail eccentric .50, shown mounted injuxtaposition to the central portion of the drive wheel (Fig. 1). This snail eccentric is designed as a slow feed for heavy drilling. The slide piece is adjustable relative to the lever by the slot 51 and the screw 52. The snail eccentric is screwed on to the threaded part of the spindle 53, the drive wheelis secured in the same manner, the spindle being retained in a position in the bearing 55 in the frame by the screw 56' (detail Fig. 6).

The projection 58 on the drilling table and the projection 59 on the frame are designed to engage with thechain 60. This chain is designed to support the drilling table in heavy drilling and it may be adjusted by a screw attachment on the frame of the brace to tighten the chain. Itis understood that minor changes may be made without depart- .ing from the scope of the invention. The

drilling table may be of various forms to suit different kinds of work.

-With this form of feed device a shallow or deep feed may be obtained. Given a large ratchet wheel with fine teeth the lever may be adjusted so thatthree teeth of the ratchet wheel 18 may be moved forward at each stroke of the lever. By another adjustment of the stroke of the lever one tooth only of the ratchet wheel may be moved forward.

This is important-for the normal feed of a feed screw for a drilling press is the thirty fifth part of a turn of the forcing screw for each rotation of the drill. When an operator is using a breast drill (often in adiifi- I cult place) it is almost impossible to turn a thread.

feed attachment by hand sufficiently fine to prevent the drill from jamming up which meansthat the operator will probably break his drill, as the slightest side movement of the operator will break a drill. The operator needs both hands to steady the breast drill.

The feed screw 16 in the present design of the machine is Attention is called to the arrangement of the lifting piece or lever 25 which is specially designed to avoid a circular motion where the ratchet 32 contacts with the ratchet teeth on the feed screw. The lifting piece 25 is designedly attached to the frame 1 of the drilling brace by the screw 26 at a point above or beyond the feed screw; which method causes the ratchet 32 which is pivotally attached to the lifting piece 25 to act in provided with a left hand' alinement with the ratchet teeth on the feed screw giving a remarkably easy motion free from j ar. A lever connected pivotallywith the frame by a bearing midway of its length could of course be used but the circular mo An ordinary cam could of course be employed in place of the snail eccentric but the snail eccentric is the most advantageous form.

What I claim is 1. A breast drill comprising a frame, a

drill spindle rotatively mounted therein, and

having a bevel pinion thereon, a hand wheel mounted on the frame, and having gear teeth for engagement with'the pinion, a rod slidably mounted on the frame, and having a work table attached to the lower end, a feed screw in engagement with said rod, a ratchet wheel mounted 011 the feed screw, ratchet mechanism mounted on the frame for actu ating the feed screw, and a cam on the said geared hand wheel for operating said ratchet mechanism. Y

2. A breast drill comprising a frame, a

drill spindle rotatively mounted therein, and

having a bevel pinion thereon, ahandwheel having gear teeth mounted on th'eframe for engaging the pinion,bearings in the'frame, a

rod slidably working in said bearings, and

having a work table attached to the lower end, a feed screw in engagement with said rod, a ratchet wheel mounted on the feed screw, ratchet mechanism mounted on a lever or lifting piece, said lever pivotally attached to the frame above or beyond the ratchet which engages the ratchet wheel,- a spring suitably connected with the framefor holding the lever in position, an adjustable stop piece for regulating the stroke of said lever,

and means on said geared hand wheel for operating the feed mechanism and giving said rod and the feed table a longitudinal motion.

PHILIP JOSHUA LE SUEUR. Signed in presence of MARIANNE MEDHURs'r,

MAY MEDHURSTJ 

